ORC - Unit 4 Part 2 Practice Exam 22/23

QT 4.1

An isolated system allows for the flow of …?

•   heat

•   kinetic energy

•   none of these

•   matter

Tags

NGSS.HS-PS3-4

QT 4.5

The volume of a piston in an internal combustion engine increases in volume by 100 ml
against a pressure of 20 atm. What is the work done?
(Conversion factor: 1 liter-atm = 100J)

• 200 J of work done on the system

• 200 J of work done by the system

• 2 J of work done on the system

• 2 J of work done by the system

QT 4.4

Which of the following statements is/are true concerning the first law of thermodynamics?

I) The internal energy (E) of the universe is conserved.

II) The internal energy of a system plus that of its surroundings is conserved.

III) The change in internal energy ( E) of a system and its surroundings can have the same sign.

• I, III

• I only

• I, II, III

• I, II

Tags

NGSS.HS-PS3-1

QT 4.6

A cell phone battery has a change in internal energy, ΔE, of 500 kJ as it powers a cell phone.  If 50 kJ of that energy warms the hand holding the cell phone, how much work was done to watch a YouTube video?

•   +450 kJ

•   -450 kJ

•   -550 kJ

•   +550 kJ

Tags

NGSS.HS-PS3-1

QT 4.7

Dr. Laude explodes a gummy bear in a bomb calorimeter. The temperature increase for the 250 grams of water surrounding the calorimeter is 20 degrees. The bomb housing has a heat capacity of 250 J/℃. How much energy is in a gummy bear? (The heat capacity of water is 4 J/g℃)

•   250 kJ

•   25 kJ

•   20 kJ

•   200 kJ

Tags

NGSS.HS-PS3-2

NGSS.HS-PS3-4

QT 4.11

Which of the following is NOT TRUE about heats of formation for a compound?

•   All reactants and products must be one mole quantities.

•   The reactants in a formation reaction are elements in their standard states.

•   Standard conditions in a formation reaction are 1 atmosphere and 298K

•   Formation reactions produce a mole of product that can be in any state

QT 4.10

Calculate the ΔHrxn for the theoretical reaction of
C ===> 2A + B
Given
C ===> B + D ΔHrxn = 200 kJ
2A ===> D ΔHrxn = -200 kJ

• 0 kJ

• 400 kJ

• -400 kJ

• 200 kJ

Tags

NGSS.HS-PS3-1

QT 4.11

What is the heat of reaction for the formation of hydrogen peroxide below given:
H2O(l) + ½O2(g) ===> H2O2(l)
the heat of formation of hydrogen peroxide, H2O2(l) , is -185 kJ/mole
the heat of formation of water, H2O(l) , is -285 kJ/mole?

• -100 kJ/mole

• Not enough information is given to solve the problem.

• -185 kJ/mole

• +100 kJ/mole

Tags

NGSS.HS-PS1-4

QT 4.13

Which of the following compounds has the greatest absolute molar entropy?

•   A mole of hexane (C₆H₁₄) in the gas phase

•   A mole of hexane (C₆H₁₄) in the liquid phase

•   A mole of cyclohexane (C₆H₁₂) in the gas phase

•   A mole of cyclohexane (C₆H₁₂) in the liquid phase

QT 4.13

Which one shows the substances in the decreasing order of their molar entropy?

•   H₂O(l) >CO₂(g) > Ne(g)  >  Ar(g)

•   CO₂(g)  >  Ar(g)  >  Ne(g)  >  H₂O(l)

•   CO₂(g) >  H₂O(l)  >  Ne(g)  >  Ar(g)

•   H₂O(l) >  Ne(g)  >  Ar(g)  >  CO₂(g)